Advanced Intermediate Beginner Home English Spanish

The Cosmic Microwave Background Radiation



A detailed view of the Cosmic Microwave Background from WMAP, compared to the original view from the COBE satellite.
Click on image for full size (86K JPG)
NASA/WMAP Science Team
In the 1960's a startling discovery was made by accident. A pair of scientists at Bell Laboratories detected some annoying background noise using a special low noise antenna. The strange thing about the noise was that it was coming from every direction and did not seem to vary in intensity at all. They had discovered the Cosmic Microwave Background Radiation.

This radiation fills the entire Universe and is no stronger or weaker in any direction. It has only tiny fluctuations that were only detected by the very sensitive space craft the Cosmic Background Explorer, COBE. This radiation is believed to be a clue to the Universe's brilliant beginning, known as the Big Bang.

More recently, the Wilkinson Microwave Anisotropy Probe (WMAP) team has made a more detailed full-sky map of this oldest light in the universe. The WMAP image brings the COBE picture into sharp focus, and provides firm answers to age-old questions. WMAP resolves slight temperature fluctuations, which vary by only a few millionths of a degree. These new data support and strengthen the Big Bang and Inflation Theories.

The Current Universe

Following in COBE's footsteps - the MAP mission

A Matter of Scale - interactive showing the sizes of things, from very tiny to huge - from NSF


Credits Settings Sponsorship Membership Contact us About the site Site map Help Myths People News Arts, books and film Images and multimedia Tours Life Geology Physics Space weather Space Missions Solar system Astronomy and the Universe Shop for science stuff Games Ask a scientist Journal Comets Dwarfs Neptune Uranus Saturn Jupiter Asteroids Mars Earth Venus Mercury Sun Teacher resources Kids Space Search Home
Last modified April 29, 2005 by Travis Metcalfe.
The source of this material is Windows to the Universe, at http://www.windows.ucar.edu/ at the University Corporation for Atmospheric Research (UCAR). © The Regents of the University of Michigan. Windows to the Universe® is a registered trademark of UCAR. All Rights Reserved. Site policies and disclaimer